Open end spinning assembly and method

ABSTRACT

AN OPEN END SPINNING ASSEMBLY AND METHOD IN WHICH PERDERABLY INDIVIDUAL FIBERS ARE SEPERATED IN A FIRST ZONE FROM A FIBROUS SUPPLY MASS TO FLOW IN A SUBSTANTALLY NONTUBULENT AIR STREAM, PREFERABLY ACCERLERATED FLOW, IN A DIRECTED PATH OF TRAVEL FOR DEPOSITION ON A SURFACE OF A ROTATING CENTRIFUGAL TURBINE FOR FIBER REMOVAL THERFROM AS A SPUN YARN IN ANOTHER ZONE REMOTE FROM THE FIRST ZONE WHERE THE FIBERS ARE INTRODUCED.

Nov. 16, 1971 P. F. GRISHIN 3,620,002

OPEN END SPINNING ASSEMBLY AND METHOD Filed March 17, 1969 INVENTOR.

PETER F. GRISHIN United States Patent O 3,620,002 OPEN END SPINNING ASSEMBLY AND METHOD Peter F. Grishin, Sanford, N .C., assignor to Roberts Company, Sanford, NC. Filed Mar. 17, 1969, Ser. No. 807,662 Int. Cl. D01h 1/12 US. Cl. 57-58.89 8 Claims ABSTRACT OF THE DISCLOSURE An open end spinning assembly and method in which preferably individual fibers are separated in a first zone from a fibrous supply mass to flow in a substantially nonturbulent air stream, preferably accelerated flow, in a directed path of travel for deposition on a surface of a rotating centrifugal turbine for fiber removal therefrom as a spun yarn in another zone remote from the first zone where the fibers are introduced.

BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION In recent years there has been increased stimulation for higher speeds of preparing yarns and attention has been directed to various improvements in open end spinning in order to achieve higher production rates with increased efficiency and maximum economy over a broad range of yarn counts with the elimination of conventional equipment. Some representative approaches to open end spinning are disclosed in US. Pats. 778,604; 1,743,601; 2,557,- 433; 3,126,697; 3,115,001; 3,368,340; and British Pat. 477,259. A vital factor in the production of a suitable spun yarn utilizing open end spinning necessitates deposition of fibers in elongated parallelization on a surface in the centrifugal turbine prior to withdrawal of the fibers to form the yarn in order to maintain uniformity and consistent strength and count throughout the linear extent of the spun yarn. The numerous variable factors involved in the production of high quality and uniform strength yarn includes the length of the staple, the speed of the centrifugal turbine, the air flow stream, the suction and positive pressures and the speeds of fibrous supply and yarn removal.

Presently available yarns produced on open end spinning systems have not been acceptable in the United States as the resulting spun yarns are of relatively low quality due to low tensile strength caused by the random orienta tion of the separate fibers constituting the yarn. Eddy currents and air drag and turbulence generated by the centrifugal turbine in the fiber introduction zone causes distortion of the incoming fibers which must fiow in the turbulent air preventing the desired parallelization in fiber flow and deposition. Generally, the velocity of air flow in different locations of the fiber inlet, channels, ducts and turbine surfaces are random and have been given little or no attention without recognizing that distortion of the fibers during movement precludes optimum fiber orientation. The random positioning of the resulting fibers can only yield a yarn of relatively low strength.

Optimum speeds of air flow operation for the centrifugal turbine and avoidance of air turbulence throughout the flow of the fibers by generating non-turbulent air flow streams which are incrementally accelerated within which 3,620,002 Patented Nov. 16, 1971 the fibers may flow will result in higher quality yarns with increased tensile strength. By causing incremental increase in air velocity while maintaining non-turbulent flow for the fibers, the fibers will tend to remain linear without curling or turning upon themselves and the fibers will be caused to flow in the extended condition to become more straightened and parallel to each other resembling fiber movement during conventional drafting whereby a fiber is straightened and becomes parallel to surrounding fibers due to the difference in the speed of the front and back drafting pairs of rollers.

Accordingly, the open end yarn spinning assembly and method of this invention is directed to providing a centrifugal turbine within which fibers may be deposited on a surface through inducing the fibers to flow in a nonturbulent air stream with increase in speeds in a directed path of travel and the removal of a spun yarn from the turbine which will have high tensile strength and uniform quality throughout.

BRIEF DESCRIPTION OF DRAWING OF A PREFERED EMBODIMENT The open end yarn spinning assembly and the method for producing yarn therefrom of this invention will be more readily understood from the following detailed description of a preferred embodiment which is intended without limitations from the following detailed description taken in conjunction with the accompanying drawing in which like characters of reference designate corresponding parts throughout the several views, and wherein:

FIG. 1 is a longitudinal sectional diagrammatic view in elevation of an open end spinning assembly embodying the apparatus and method of this invention with portions removed;

FIG. 2 is a transverse sectional view taken substantially along the plane of section line 22 of FIG. 1;

FIG. 3 is a transverse sectional view, reduced in scale, taken substantially along the plane of section line 33 of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to'the drawing and particularly to FIG. 1, there is illustrated a pair of delivery rolls 10 of a drafting system for discharging substantially parallel and separated fibers 11 from a fibrous supply mass 12 which fibrous mass could be drawn from a sliver or roving. The fibers are introduced into the cylindrical, narrow inlet duct 13 with the upper end 14 of duct 13 reaching preferably between the rolls 10 to receive the fibers and through induced suction, to be described hereafter, the fibers 11 are drawn into the inlet 15 of duct 13. Preferably the length of duct 13 should be substantially equal to or shorter than the average fiber length. The duct 13 is provided with an axial opennig 16 through which the fibers 11 pass downwardly. Duct 13 is provided with a base flange 17 through which there are drilled a plurality of outer openings 18 and inwardly inclined openings 19 through which openings 18 and 19 and opening 16 air may flow downwardly through the frusto-conical chamber 20 formed by the tubular shell or housing 21 that is securely fastened by the projecting flow. It is extremely desirable to have the air speed increase incrementally throughout chamber from the inlet to the discharge to elongate or cause the individual fibers 11 to flow in the fully extended form.

A substantially conical head is supported on the housing 21 through the axially spaced-apart bearings 26 which permit the conical head 25 to revolve by the driving contact of belt 27 on the crowned perimeter 28 on the pulley 29. However, conical head 25 may be retained in a non-rotating condition or it may be permitted to rotate through air friction and currents generated by the rotation of the centrifugal turbine 30. A downwardly divergent skirt 31 depends from the conical head 25 with the terminal end 32 of the skirt 31 extending into the upper section 33 of turbine through the open top 34 thereof. The divergent skirt 31 is provided with one or a series of passageways of internal ducts 36, separated from each other, through which air will flow continuously tending to straighten the fibers 11 with the ducts 36 communicating with the conical head plenum chamber 37 from which also extends axially the downwardly converging duct 38 through which no fibers are intended to flow normally. The open terminal end 39 in each of the ducts 36 will permit the fibers 11 to flow therethrough for deposite in parallel alignment substantially on the surface of the centrifugal turbine 30. The air velocity from the design of the chamber 20 is such that the nonturbulent flow of air will straighten out or extend a fiber 11 rectilinearly substantially so that the air velocity at one end B of the fiber is greater than the air velocity at end A, as shown in chamber 20, tending to straighten out the fiber as it flows along a directed path of travel through chamber 20, plenum chamber 37, duct 36 through opening 39 to be deposited on surface 35 in the upper section 33 of centrifugal turbine 30.

Turbine 30 is divided into upper section 33 and lower section 40 formed by the frusto-conical downwardly converging wall 41 in which there is a series of circumferentially spaced-apart openings 42 which are substantially radial or diverge upwardly and rearwardly for the release of any air pressure within the interior of the centrifugal turbine 30. A circular ring 43 is formed at the intersection of wall 35 and wall 41. The surface of wall 35 is sufficiently smooth to permit maintenance of parallelization of the fibers when deposited and sliding thereof when subjected to centrifugal force to be displaced toward the ring 43, ultimately to be removed in the form of a spun yarn 44 which will be formed of the fibers deposited on wall 35.

Rotation of the conical head 25 occurs with the aid of the belt or tape 27 but, when released, will rotate because of the air friction against the bottom surface 45 thereof generated by the air rotating in centrifugal turbine 30.

Turbine 30 is provided with an upwardly extending boss 46 that is bored axially to receive cooperatively for support thereon the centrifugal turbine drive shaft 47 that is supported for vertical rotation in the axially spacedapart bearings 48 that are mounted in the frame-supported yoke 49. A shaft driving belt 50 engages the shaft mounted pulley 51 for rotating the shaft 47 about a vertical axis for rotating turbine 30 therewith as the turbine boss 46 is securely fastened to shaft 47. An axial yarn passageway 52 is provided in shaft 47 through which the yarn 44 may be withdrawn. Yarn 44 is continuously withdrawn by the rotation of the discharge rolls 54 positioned in alignment with the yarn passageway 52 in shaft 47. The bulk and fineness of the yarn will be determined by the various speeds of the fiber delivery rollers 10 and discharge rolls 54.

As an alternate construction, the shaft 47 may be stationary or fixed and a drive pulley (not shown) attached directly to the turbine 30 through a downward extension (not shown) of the boss or sleeve 46 to rotate the turbine 3t).

To commence spinning, a previously formed yarn is inserted manually upwardly through the yarn passageway 52 into the centrifugual turbine lower section 40 after fibers have been deposited on surface 35 of the rotating turbine. The air stream flowing in the turbine will lead the inner free end of the inserted yarn into the proximity of the ring 43 and the inserted yarn will rotate with the turbine to gather the fibers adjacent to the ring 43 from the surface 35 and the fibers will cling to the free end and commence to accumulate additional fibers thereby forming a new spun yarn continuously as the outer depending previously formed yarn is inserted into the delivery rolls 54 to commence continuous operation.

The configuration of the ducts 36 is conical to maintain the increased air speed previously referred to throughout the directed path of travel of the fibers 11 until the fibers are deposited on the surface 35. The movement of the air and the fibers downwardly through chamber 20 and ducts 36 is caused by the centrifugal force of rotation generated from the rotation of the centrifugal turbine 30. However, when the conical head 25 is rotated. additional movement of air and fibers will result. Turbulence of air is further reduced by the vacuum generated in duct 38 upon rotation of turbine 30 which will augment the induced suction through inlet duct 30, chamber 20, plenum 37 and ducts 36.

I claim:

1. An open end yarn spinning assembly for receiving fibrous material fed from a fibrous source thereto and discharging a spun yarn therefrom comprising: a rotatable centrifugal turbine having a fiber-receiving wall and generating air flow therethrough, means for rotating said turbine, and fiber inlet means for conveying fibers to said turbine by means of air fiow, said fiber inlet means defining at least one air flow passage of continuously narrowing cross section from input to output for gradually incrementally increasing air fiow velocity throughout said at least one passage without turbulence for guiding fibers in elongate, parallel form to said fiber-receiving wall for removal therefrom as a spun yarn, said fiber inlet means including a stationary member and a rotatable member, each defining an air flow passage therethrough.

2. An open end yarn spinning assembly as claimed in claim 1, and further including means for driving said rotatable member.

3. An open end yarn spinning assembly as claimed in claim 2, said rotatable member being driven at a speed substantially greater than the speed of said turbine.

4. An open end yarn spinning assembly as claimed in claim 1, said fiber inlet means rotatable member having a depending passage for non-turbulent flow of air and fibers extending into said centrifugal turbine to discharge fibers on said fiber-receiving wall.

5. An open end yarn spinning assembly as claimed in claim 1, said fiber inlet means rotatable member including a plurality of depending passages extending into said centrifugal turbine for delivering extended and parallel fibers to said fiber-receiving wall.

6. An open end yarn spinning assembly as claimed in claim 1, and means for rotating said rotatable member defining an air flow passage therethrough to deposit fibers on said fiber-receiving wall.

7. An open end spinning assembly as claimed in claim 1, said fiber inlet means rotatable member passage extending substantially radially into said centrifugal turbine to deposit fiber on said fiber-receiving wall thereof.

8. The method of forming a spun yarn from fibers in an open end spinning system comprising the steps of: introducing fibers into a first supply zone, conveying the fibers along a rotating directed path of travel in a substantially non-turbulent air stream having incrementally increasing velocities to straighten and parallelize the fibers during flow along a directed path of travel, depositing the fibers in straightened and parallel alignment on a revolving surface, and removing the fibers therefrom as a spun yarn.

References Cited UNITED STATES PATENTS 2,853,479 9/1958 Keeler et a1 5758.89 X 3,115,001 12/1963 Cizek et a] 5758.91 3,254,482 6/1966 Stalego 5758.89 X

3,411,283 11/1968 Isomura 57-58.89

3,481,129 12/1969 Shepherd et a1 5758.89

FOREIGN PATENTS 1,468,231 12/1966 France 5758.95

U.S. Cl. X.R. 

